Pressure intensifier



March 5, 1963 e. H. DRUTCHAS ETAL 3,079,354

PRESSURE INTENSIFIER Filed Sept. 10, 1959 RETURN BESE RVOIE [EVEN/0P5 G/L/QEP7 A4 02070445 #0259744 CLARK FLOW PRESSURE 1 7 f7 2 W Z,/V% 57 ilnited rates 3,979,864 PRESSURE HNTENSIFER Gilbert H. Drutchas, Detroit, and Hubert M. Clark,

Bloomfield Township, Gakland County, Mich, assignors to Thompson Raine Wooidridge, lnc., Cleveland,

Ghio, a corporation of Ohio Filed Sept. 10, 1959, Ser. No. 833,171 1 Claim. ((31. 10357) This application constitutes a continuation-in-part of our earlier application Serial No. 814,516, filed May 20, 1959, now abandoned and the subject matter of which is merged with our copending application Serial No. 27,622, filed May 9, 1960.

This invention relates to a pressure intensifier and more specifically to the use of a slipper piston type pump wherein an annular outer stage acts as an hydraulic motor to cause rotation of the motor and to impart a radial pumping action to the slippers and wherein the inner sides of the slippers are charged with fluid at inlet pressure which is forced out at an increased or intensified pressure for supply to a point of utilization.

It is an object of the present invention to provide improved pressure intensification means.

Another object of the present invention is to accomplish a new use of a slipper piston type pump.

Yet another object is to provide an hydraulic system wherein an excellent high pressure source is readily available for use in charging an hydraulic accumulator or the like.

Many other advantages, features and additional objects of the present invention will become manifest to those versed in the art upon making reference to the detailed description which follows and the accompanying sheet of drawings in which a preferred structural embodiment of a pressure intensifier is shown by way of illustrative example incorporated in an hydraulic circuit which, by way of illustration, includes an accumulator.

On the drawings:

FIGURE 1 is a schematic view of an hydraulic circuit and shows in the circuit a pressure intensifier in cross-section in a sectional plane taken on line I-I of FIGURE 2; and

FIGURE 2 is a cross-sectional view taken substantially on line II-1I of FIGURE 1.

As shown on the drawings:

The pressure intensifier of the present invention is for the purpose of converting a portion of a pressurized fluid flow such as a low pressure oil flow into a fluid flow at intensified pressure, for example, a high pressure oil flow which may be used to charge an hydraulic accumulator or the like.

The objects of the invention are effectively accomplished by the use of a slipper-piston-type pump indicated generally at as comprising a casing 11 forming a housing for the intensifier in which is formed an inlet 12 and an outlet 13.

As shown in FIGURE 1, the inlet 12 is connected to receive fluid at increased pressure since the intensifier 10 is incorporated in the hydraulic circuit and in FIGURE 1 there is shown by legend a pressure fiow leading to the inlet 12.

A working chamber 14 is formed in the housing 11 and includes a generally cylindrical bore formed by a bore wall 16 recessed on one side of the intensifier to provide an inlet recess 17 and recessed on the opposite side of the intensifier to provide an outlet recess 18.

The casing forming the housing 11 is closed by a cover member 19 retained in firm assembly with the housing 11 by a plurality of fasteners indicated at 29. In accordance with the principles of the present invention, there is provided between the inlet 12 and the outlet 13 a gen- Patented Mar. 5, 1953 erally cylindrical rotor 21 having an outer peripheral surface 22 which is of lesser diameter than the inside diameter of the bore wall 16.

The rotor 21 is particularly characterized by the formation in the peripheral surface 22 of a plurality of circumferentially spaced notches, recesses or slots herein indicated at 23 and which may be rectangular in cross-sectional configuration as prescribed by spaced apart side walls 24 and 26 extending radially inwardly from the outer peripheral surface 22 and terminating in a bottom wall 27.

Each slot 23 receives a slipper-type element indicated generally at 28 which is generally free to move radially and to rock angularly. As shown in the drawings, each element forming the slipper means 28 is of a generally U-shaped configuration in cross-sectional shape including a bight portion 29 forming a contact area 31 for engaging against the bore wall 16. Each slipper element 28 further includes spaced leg portions indicated at 31 and 32, respectively, the side wall of the leg 31 being indicated at 33 and the side wall of the leg 32 being indicated at 34. The side walls 33 and 34 diverge somewhat in outward direction and terminate in end portions adapted to slidably engage against the adjoining walls 24 and 26 of a corresponding slot 23.

Bottomed against the inside of the bight portion 29, as indicated at 36, is a coil spring 37 having its opposite end engaged against an adjoining bottom wall 27 ofa corresponding slot 23. Thus, each slipper element 28 is preloaded in radially outwardly extending direction so the contact area 3% will engage and follow the adjoining wall 16 of the working chamber 17.

In order to rotate the rotor 21 on a rotational axis 011- set from the center axis of the working chamber 14, there is provided a boss 38 in the housing 11 through which extends a shaft passage 39 carrying a pair of spaced bearings 4!] and 41 which, in turn, rotatably support a shaft indicated at 42. The shaft 42 has connected therewith a coupling member 43 splined as at 44 to the rotor 21.

The rotational axis of the shaft 42 is eccentrically 0&- set with respect to the center axis of the bore wall 1s, thereby providing between the housing 11 and the rotor 21 a sealing area 46 extending between the inlet and the outlet 12 and 13 and further forming a crescent-shaped working area 47 which extends from one side of the intensifier adjacent the inlet 12 and its corresponding inlet recess 17 and the outlet 13 and its corresponding outlet recess 18 on the other side of the intensifier. Thus, the housing 11 together with the slipper-carrying rotor 21 forms an outer annular stage which acts as an hydraulic motor responsive to the supply of pressurized fluid into the inlet 12 so that the rotor 21 is rotatably driven and during such rotation the slipper means 18 are given a radial pumping action. Thus, when the rotor 21 is rotatably driven in response to pressure fluid flow, the slipper elements 23 which are continuously biased into engagement with the bore wall 16, will follow the contour prescribed by the bore wall 16 and the pressurized fluid in passing or flowing through the crescent-shaped working area 47 between the inlet 12 and the outlet 13 will hydraulically actuate the slipper-carrying rotor 21 for rotatable operation.

As further provided in accordance with the principles of the present invention, the housing 11 has formed therein an arcuate inlet slot 5% on the inlet side of the pump and an arcuate outlet slot 51 on the outlet side of the pump. The inlet slot 511 is formed to be disposed generally radially inwardly or" the slipper elements 23 and further extends at least partially radially outwardly of the bottom wall 27 of each respective notch or slot 23.

The outlet slot 51, on the other hand, is positioned radially inwardly of the bottom wall of the notches 27. Accordingly, to estab ish communication between the outa let port 51 and the inside of the slipper elements 28, the face of the rotor 21 adjacent the ports 50' and 51 is formed with passage means 69.

The housing 11 further includes a passage 52 which extends between the inlet slot St} to the working chamber 47 adjacent the inlet recess 17, thereby permitting the inher side of the slippers to be charged'with fluid at increased pressure and at the pressure present in the inlet port 12.

Also formed within the housing 11 is a passage 54 which connects the outlet slot 51 to appropriate means leading to a point of utilization such as an accumulator identified by legend and further identified by the reference numeral 61.

Although the rotor 21 is herein illustrated as containing four notches and four slippers, it will be understood that the amount of fluid which is pumped into the high pressure port 51 may be controlled by the number and the stroke of the slipper elements 28 provided, as well as by the width and length of such slipper elements. Accordingly, the number and arrangement of the slippers in the rotor, as herein disclosed, is merely exemplary of the inventive principles forming the basis of this disclosure.

7 It has been determined that intensification accomplished by the practice of the present invention is in accordance with the following.

Assuming a low pressure flow of gallons per minute at 100 pounds per square inch through the hydraulic circuit and hence through the inlet 12, the working chamber 47 and the outlet 13, and further assuming a high pressure flow ratio of 20 of the lowpressure flow through the passage 52, the port 50, the port 51 and the passage 54, the amount of intensification would be 5 gallons per minute times 100 pounds per square inch divided by 20% of 5 gallons per minute equals 500 pounds per square inch. Thus, the intensification of 5 times would increase the pressure from 100 psi. to 500 p.s.i., an adequate quantum of pressure increase for effective utilization in charging an hydraulic accumulator or the like.

In formula form, such intensification is represented by the following formula:

wherein P =intensified pressure P =pressure of fluid at increased pressure V =volume of flow of fluid at increased pressure V =volume of flow of fluid at intensified pressure.

ing element is retracted into the slot 23, thereby to mini mize the volume thereof.

As the rotor 21 carries a slipper element 28 past the inlet side of the intensifier, the slipper element starts to move radially outwardly so the volumetric area defined between the bottom of the slot 23 and a slipper element 28 increases to condition the inner side of the slipper to be charged with low pressure through the passage 52.

"As the slipper elements 28 are carried past the outlet side of the pump, the volumetric area again decreases.

Accordingly, the rotation of the rotor 21 imparts a radial in and out pumping action to the slipper elements 28 and such pumping action results in the intensification of the fluid in the manner described above.

In order to assist in developing an adequate seal between the pumping circuits 12, 13 and 50, 51, the pumping elements or slipper elements 28 may be provided with a sealing means. In the arrangement illustrated, one of the side walls of each notch, for example, the side wall 26 is recessed as at 65 and receives a pin 66. The recess 6'5 and the pin 66 may be of a length corresponding in length to the slipper element 28. Thus, the pin 66 fits in the recess 65 and has a portion extending outwardly of the wall 26 to engage against the adjoining side wall 34- of a corresponding slipper element 28. I Although the slipper element 28 is free to conformably engage'the bore wall 1d of the housing and is also free to move radially in the slot 23 and to rock angularly, the pin 66 assists in controlling leakage between the separated pumping circuitsexisting between the inlet 12 and the outlet 13 and between the inlet 50 and the outlet. 51. The pin 66 is, in effect, centrifugally responsive and self-energized because the sealing function efiected thereby is improved during operational rotation.

Although minor modifications might be suggested by those versed in the art, it should be understood that we wish to embody within the scope of the patent warranted hereon all such modifications as reasonably and properly come within the scope of our contribution to the art.

We claim as our invention:

A combined motor and pressure intensifying pump comprising a casing having a cylindrical bore wall,

a rotor rotatable on an offset axis in said casing, thereby providing with said cylindrical bore wall a crescent-shapedworking chamber between said rotor and said bore wall,

means forming one or more peripheral axially extending recesses in said rotor each having generally par allel side walls and a bottom wall,

a slipper in each said recess having a radial outer sealing surface curved to engage the adjoining bore wall with surface contact and including first and second side walls disposed adjacent said side walls of. said recess,

said first and second side walls being shaped to permit said slipper to rock andltomove inwardly and outwardly of said recess in following the bore wall, said first side wall of said slipper engaging' the adjoining side wall of said recess, means forming a sealing pin interposed between said second side wall of said slipper and the other side wall of said recess, a sealing pin recess in one of said side .walls receiving said sealing pin, means forming sealing surfaces radially outwardlyof said sealing pin on said slipper and on said rotor against which said sealing pin is engaged inv sealing relation in response tocentrifugal force, thereby tov seal the working chamber from .the. radially inner portions of each said recess,

an. inlet port formed in. said casing receiving fiuidxat increased pressure and discharging said fluid into said working chamber to rotatably drive said rotor in said casing by acting on'said slipper, an outlet port in said casing receiving spent fiuidfrom said chamber, 7

said casing having an inlet passage extending from said inlet port radially inwardly to communicate with each said recess radially inwandly of a corresponding slipper, thereby to fill each said recess behind each corresponding slipper with fluid under pressure, and a separate outlet port for connection to an accumulator or a point of utilization of fluid at intensified pressure and formed in said casing on the outlet side of said casing for communication with said recess to receive the fluid at an intensified pressure (References on following page) References Cited in the file of this patent UNITED STATES PATENTS Nichols Oct. 29, 1889 Wood Aug. 9, 1904 Ostrander July 7, 1908 Storey Feb. 21, 1922 Phillips May 27, 1924 Brightwell Nov. 16, 1937 6 Links Sept. 14, 1954 Deschamps May 24, 1955 McVeigh Oct. 22, 1957 Livermcre et a1 Nov. 21, 1961 FOREIGN PATENTS Italy Sept. 9, 1947 France Feb. 26, 1940 

